I have created a family of related inventions at least one of which is disclosed in U.S. Pat. No. 3,857,450 issued December, 1974. It has been my purpose to systematically evolve a series of revolutionary well tools for the manipulation of drill pipe to propel the rotary drilling art out of its developmental stagnation in which it has been mired from the early part of this century. Every element of the conventional drilling tools has been carefully studied by myself and their consolidations, replacements and improvements have been scattered throughout the complete range of these improved tools as used in the drilling operation.
The lowly slip structures have not escaped by analysis. I have provided a carriage structure for these manually manipulated slip structures to facilitate their movement on the rig floor. The placing of the slips has been shifted and their structure has been modified in my striving toward ultimate simplicity, speed and flexibility in the dangerous handling of drill pipe as it has been made up into drill strings and tripped in and out of the well.
The concept of automation is the lode star in drill pipe handling. However, I have made my improvements as a compatible extension of the prior art. In the present instance, it is my desire to automate the entire slip structure as the upper end of the drill string is brought up through the opening in the floor of the drill rig for the standard rotary table. The problem I face is the provision of what I call a "spider" structure which can be automated to grip and release the drill string as it is brought up from the well, but with the spider mounted at the existing aperture in the rig floor.
Some form of adapter plates must be provided to fit the standard openings in regular floors where the removed rotary table was located. These plates, or plate, must be adapted to support the improved automated spider structure which I provide. The spider structure must include the concept of a pair of jaws closed beneath the shoulder of the box on the upper end of the top drill string stand. At the same time, the two jaws of the spider must be manually or automatically actuated to open and release the drill string as required in the drilling and tripping sequences.